3.1.9 Inorganic Ions

Question 1

State where inorganic ions can be found in the body.

Answer 1

1. Occur in solution in the cytoplasm and body fluids of organisms.
2. Some in high concentrations and others in very low concentrations.

Question 2

Phosphate Ions– PO43-

Answer 2

1. Attached to other molecules as a phosphate group.
2. Phosphate ions form the phosphate groups of DNA/RNA nucleotides.
3. Enables nucleotides to join together – phosphodiester bonds form.
4. Phosphate ions form the phosphate groups of ATP - Breaking the bonds between the phosphate groups in ATP releases energy.

Question 3

SODIUM IONS

Answer 3

Co transport of glucose and amino acids across cell membranes.

Question 4

HYDROGEN IONS

Answer 4

1. Maintain pH levels in the body. * Too much H+ = acidic (low pH).
2. Too little H+ = alkaline (high pH).
3. Affects rate of enzyme controlled reactions as can cause enzymes to denature.

Question 5

IRON IONS

Answer 5

1. Component of (haem group of) haemoglobin which is contained in red blood cells.
2. Transports oxygen around the body – oxygen temporarily binds to it so it becomes Fe3+.